The ubiquity of computers in business, government, and private homes has resulted in the availability of massive amounts of information from network-connected sources, such as data stores accessible through communication networks. In recent years, computer communication and search tools have become widely available to facilitate the location and availability of information to users. Most computer communication and search tools implement a client-server architecture, where a user client computer communicates with a service provider via a remote server computer over a communication network.
One approach to increasing service provider communication bandwidths relates to employing multiple network server computers offering the same services. These server computers may be arranged in server farms, in which a single server from the server farm receives and processes a particular request from a client computer. Typically, server farms implement some type of load balancing algorithm to distribute requests from client computers among the multiple servers. Generally described, in a typical client-server computing environment, client devices generally issue requests to server devices for some kind of service and/or processing, and the server devices process those requests and return suitable results to the client devices. In an environment where multiple clients send requests to multiple servers, workload distribution among the servers significantly affects the quality of service that the client devices receive from the servers.
Central control of load balancing typically requires a dedicated hardware controller, such as a master server, to keep track of all servers and their respective loads at all times. Alternatively, the central communication processing component may be a communication processing device that uses a simple algorithm, such as a round-robin load distribution algorithm, to distribute client requests over several servers. The communication load resulting from client requests affects not only the servers that serve the client requests, but also the hardware communication processing components which have to route the client requests. Because the communication loads affect the communication processing components, an efficient and effective load balancing solution must take into account the load imposed on hardware load balancing components, as well as the servers which service client requests.
One approach is to use a server locator service (SLS) for handling client requests. In this approach, the client request is directed to a well-known name or internet protocol (IP) address for service. The communication processing component queries SLS services running on multiple servers to locate a server to service the client request. The communication processing component is actually distributing the communication load over the SLS services and not the services requested by the client computing device. Once a host is located, the host name is returned to the client computing device for further client service requests. In this approach, the first client request is a discovery request which, as noted above, is directed to the SLS services running on the servers. Discovery requests do not include data requests and are only used to locate servers. Such discovery requests are out-of-band communications, meaning that discovery requests do not pass through the same logical communication channels as data requests. Out-of-band communication incurs certain overhead costs, such as additional communication related to the discovery packets which do not contribute to transmission of data.